The Mountain States (also known as the Mountain West and the Interior West) form one of the nine geographic divisions of the United States that are officially recognized by the United States Census Bureau. It is a subregion of the Western United States. The Mountain States are usually split up into two other regions known as the Northwest and Southwest. Idaho, Montana, and Wyoming are considered part of the northwest, while Arizona, New Mexico, Colorado, Nevada, and Utah are considered part of the southwest.
The division consists of eight states: Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, and Wyoming. These eight states have the highest mean elevations of all 50 U.S. states. Together with the Pacific States of Alaska, California, Hawaii, Oregon and Washington, the Mountain States constitute the broader region of the West, one of the four regions the United States Census Bureau formally recognizes (the Northeast, South and Midwest being the other three). The word "Mountain" refers to the Rocky Mountains, which run north-south throughout portions of the states of Montana, Idaho, Wyoming, Colorado, Utah, and New Mexico. Arizona and Nevada, as well as other parts of Utah and New Mexico have other smaller mountain ranges and scattered mountains located in them as well.
Mountain Time is observed in nearly the entire division, except Nevada (all but the stateline city of West Wendover) and the Idaho Panhandle. Daylight saving time is not observed in Arizona, except for lands within the Navajo Nation (Northeast corner of the state) which observe daylight saving time due to the Nation traversing state lines. For this reason, most of Arizona is one hour behind the rest of the Mountain Time Zone from the second Sunday in March until the first Sunday in November.
Regional geography 
The Mountain West is one of the largest and most diverse regions in the United States. Most regional boundaries of the Mountain West are often looked at as the area from the High Plains to the Sierra Nevada Mountains and Cascade Mountains. Although, the southern and northern portions of the Mountain West are often split into two separate regions. The Southern portion (Arizona, New Mexico, Utah, Colorado, and Nevada) are often called the greater Southwest region. Meanwhile, the northern portion (Wyoming, Idaho, and Montana) are often either called Northwest states or the Northern Mountain West region.
The terrain of the Mountain West is more diverse than any other region in the United States. Its physical geography ranges from some of the highest mountain peaks in the continental United States, to large desert lands, and flat rolling plains in the eastern portion of the region. The mountain west states contain all of the major deserts found in North America. The Great Basin Desert is located in most all of the Nevada, Western Utah, Southern Idaho, and Southern Oregon. Wyoming also has a vast amount of desert land in the southwestern portion of their state, which is known as the Red Desert. Portions of the Mojave Desert are located in California, but over half of the desert is located in southern Nevada, in the mountain west. Meanwhile, the Sonoran Desert is located in most all of Arizona and the Chihuahuan Desert is also located in most of Southwestern and Southern New Mexico. Colorado has scattered desert lands in the southern, and northwestern portions of the state.
Colorado, New Mexico, Utah, and Arizona also have other smaller desert lands, which are part of the Colorado Plateau desert lands. The Painted Desert is located in Northern and Northeastern Arizona, and the San Rafael Desert is also located all over Eastern Utah. New Mexico also has other desert lands located in Northern and Northwestern New Mexico. Also, Colorado has large desert lands on the Colorado plateau in Northwestern, Western, and Southern Colorado. These desert lands in Colorado are located in and around areas such as, the Royal Gorge, Great Sand Dunes, Pueblo, San Luis Valley, Cortez, Dove Creek, Delta, Canyon of the Ancients National Monument, Roan Plateau, Dinosaur National Monument, Colorado National Monument, and the Grand Mesa. The San Luis Valley is well known as the largest high valley desert in the world.
In the far eastern portions of the Mountain West, there are the High Plains area of the Great Plains. These plains mainly consist of flat rolling land, with scattered Buttes, canyons, and forests located in these areas. Even though these plains areas are part of the Great Plains, they are not part of the same region. Reasons for this is that the High Plains receive very little rainfall and sit at high elevations usually about 3,000 to 6,000 feet. Many people view the High Plains as the point where you begin to enter the greater Mountain West region.
The Mountain West also has some of the highest mountain peaks in America. Some of the more famous mountains in the Mountain West are Mount Elbert, Pikes Peak, Blanca Peak, Longs Peak, Kings Peak, Wind River Peak, Cloud Peak, Wheeler Peak, Truchas Peak, Granite Peak, Borah Peak, and Humphreys Peak.
The climate of the Mountain West is also one of the more diverse climates in the United States. The entire region generally features a semi-arid to arid climate, with some alpine climates in the mountains of each state. Some parts of the tall mountains can receive very large amounts of snow and rain, while other parts of the region receive very little rain and virtually no snow at all. The High Plains in the eastern portion of the region receive moderate snow falls, but virtually very little rain at all.
The states of Nevada and Arizona are generally filled with desert lands and scattered mountain ranges. Much of Nevada receives little to no snow in the southern portion of the state, while Northern Nevada can receive large amounts of snow in and around the mountains, and even in the desert lands in Nevada. Arizona generally receives little rain or snow, but high elevations in and near mountains receive extremely large amounts of rain and snow. Northern and Northeastern Arizona display characteristics of a "High Desert", where the summers are very hot and dry, while the winters can become very cold and it can snow as well.
Utah is also generally large desert lands with mountains as well. However, the desert lands in Utah receive significant snow falls in the desert lands, and also large snow falls in and around the mountains. Colorado and New Mexico have very similar climates. Both states can receive significant snow falls off the mountains, while the mountains in both states receive extremely large amounts of snow. However, southern and southwestern New Mexico generally does not receive much snow at all, similar to southern Nevada and southern Arizona. The desert lands found in northeastern Arizona, eastern Utah, northern New Mexico, western and southern Colorado are also generally referred to as the "High Desert" lands.
The Northern portion of the Mountain West tends to be a bit cooler than the southwestern areas. Wyoming, Idaho, and Montana all receive significant snow falls off the mountains and very large snow falls in the mountains as well. The High Desert also exists in the northern mountain west. Southeastern Oregon, southern Idaho, and southwestern Wyoming have the Great Basin Desert lands located in them, which is part of the high desert.
|Rank||State||2010 pop||2000 pop||Change||Capital||Most populous city|
|3||Utah||2,763,885||2,233,169||+23.77%||Salt Lake City||Salt Lake City|
|4||Nevada||2,700,551||1,998,257||+35.15%||Carson City||Las Vegas|
|5||New Mexico||2,059,179||1,819,046||+13.20%||Santa Fe||Albuquerque|
|Rank||State||Highest point||Highest elevation||Lowest point||Lowest elevation||Mean elevation||Elevation span|
|Arikaree River at Kansas border||
|Belle Fourche River at South Dakota border||
|Beaver Dam Wash at Arizona border||
|4||New Mexico||Wheeler Peak||
|Red Bluff Reservoir on Texas border||
|Colorado River at California border||
|Snake River at Washington border||
|Colorado River at Sonora border||
|Kootenai River at Idaho border||
|Mountain States||Mount Elbert||
|Colorado River at Sonora border||
|Rank||Municipality||State||2010 pop||2000 pop||Change|
|14||North Las Vegas||Nevada||216,961||115,488||+87.86%|
|17||Salt Lake City||Utah||186,440||181,743||+2.58%|
|22||West Valley City||Utah||129,480||108,896||+18.90%|
Urban Areas 
|Rank||CBSA||2010 pop||2000 pop||Change|
|1||Phoenix-Mesa-Glendale, AZ MSA||4,192,887||3,251,876||+28.94%|
|2||Denver-Aurora-Broomfield, CO MSA||2,543,482||2,179,240||+16.71%|
|3||Las Vegas-Paradise, NV MSA||1,951,269||1,375,765||+41.83%|
|4||Salt Lake City, UT MSA||1,124,197||968,858||+16.03%|
|5||Tucson, AZ MSA||980,263||843,746||+16.18%|
|6||Albuquerque, NM MSA||887,077||729,649||+21.58%|
|7||Colorado Springs, CO MSA||645,613||537,484||+20.12%|
|8||Boise City-Nampa, ID MSA||616,561||464,840||+32.64%|
|9||Ogden-Clearfield, UT MSA||547,184||442,656||+23.61%|
|10||Provo-Orem, UT MSA||526,810||376,774||+39.82%|
|11||Reno-Sparks, NV MSA||425,417||342,885||+24.07%|
|12||Fort Collins-Loveland, CO MSA||299,630||251,494||+19.14%|
|13||Boulder, CO MSA||294,567||269,814||+9.17%|
|14||Greeley, CO MSA||252,825||180,926||+39.74%|
|15||Prescott, AZ MSA||211,033||167,517||+25.98%|
|16||Las Cruces, NM MSA||209,233||174,682||+19.78%|
|17||Lake Havasu City-Kingman, AZ MSA||200,186||155,032||+29.13%|
|18||Yuma, AZ MSA||195,751||160,026||+22.32%|
|19||Pueblo, CO MSA||159,063||141,472||+12.43%|
|20||Billings, MT MSA||158,050||138,904||+13.78%|
|21||Grand Junction, CO MSA||146,723||116,255||+26.21%|
|22||Santa Fe, NM MSA||144,170||129,292||+11.51%|
|23||Coeur d'Alene, ID MSA||138,494||108,685||+27.43%|
|24||Saint George, UT MSA||138,115||90,354||+52.86%|
|25||Flagstaff, AZ MSA||134,421||116,320||+15.56%|
|26||Sierra Vista-Douglas, AZ μSA||131,346||117,755||+11.54%|
|27||Idaho Falls, ID MSA||130,374||101,677||+28.22%|
|28||Farmington, NM MSA||130,044||113,801||+14.27%|
|29||Logan, UT-ID MSA||125,442||102,720||+22.12%|
|30||Missoula, MT MSA||109,299||95,802||+14.09%|
|31||Show Low, AZ μSA||107,449||97,470||+10.24%|
|CSA||2010 pop||2000 pop||Change||Component CBSAs|
|Denver-Aurora-Boulder, CO CSA||3,090,874||2,629,980||+17.52%||Denver-Aurora-Broomfield, CO MSA
Boulder, CO MSA
Greeley, CO MSA
|Las Vegas-Paradise-Pahrump, NV CSA||1,995,215||1,408,250||+41.68%||Las Vegas-Paradise, NV MSA
Pahrump, NV µSA
|Salt Lake City-Ogden-Clearfield, UT CSA||1,744,886||1,469,474||+18.74%||Salt Lake City, UT MSA
Ogden-Clearfield, UT MSA
Brigham City, UT µSA
Heber, UT µSA
|Reno-Sparks-Fernley, NV CSA||477,397||377,386||+26.50%||Reno-Sparks, NV MSA
Fernley, NV µSA
|Santa Fe-Espanola, NM CSA||184,416||170,482||+8.17%||Santa Fe, NM MSA
Espanola, NM µSA
|Clovis-Portales, NM CSA||68,222||63,062||+8.18%||Clovis, NM µSA
Portales, NM µSA
Politics of the Mountain States 
See also 
- Mountain Time Zone
- Rocky Mountains
- United States
- Table of United States Combined Statistical Areas
- Table of United States Core Based Statistical Areas
- U.S. state
- Western United States
- http://www.infoplease.com/spot/daylight1.html Infoplease: Daylight Saving Time, A trip around the world reveals that time isn't a synchronized science
- "The American FactFinder". 2010 United States Census. United States Census Bureau, Population Division. Retrieved October 17, 2011.
- See the List of U.S. states by elevation.
- "Mount Elbert". NGS data sheet. U.S. National Geodetic Survey. Retrieved October 20, 2011.
- "Gannett Peak Cairn". NGS data sheet. U.S. National Geodetic Survey. Retrieved October 20, 2011.
- "Kings Peak Target". NGS data sheet. U.S. National Geodetic Survey. Retrieved October 20, 2011.
- "Wheeler". NGS data sheet. U.S. National Geodetic Survey. Retrieved October 20, 2011.
- "Boundary". NGS data sheet. U.S. National Geodetic Survey. Retrieved October 20, 2011.
- "Beauty Reset". NGS data sheet. U.S. National Geodetic Survey. Retrieved October 20, 2011.
- "Frisco". NGS data sheet. U.S. National Geodetic Survey. Retrieved October 20, 2011.
- "Granite Peak". NGS data sheet. U.S. National Geodetic Survey. Retrieved October 20, 2011.
- "OMB Bulletin No. 10-02: Update of Statistical Area Definitions and Guidance on Their Uses". United States Office of Management and Budget. December 1, 2009. Retrieved October 18, 2011.
- The Sacramento—Arden-Arcade—Yuba City, CA-NV Combined Statistical Area includes the Gardnerville Ranchos, NV Micropolitan Statistical Area, but is located primarily in the State of California.
|Wikimedia Commons has media related to: Mountain States|
- United States government
- Western Governors Association